Apparatus and method for wireless communications

ABSTRACT

An apparatus and method for wireless communications are provided. The apparatus for wireless communications includes a media access control processing unit providing a plurality of sub-packets, and a transmitting/receiving unit outputting a packet that includes the plurality of sub-packets using a plurality of transmission modes.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from U.S. Provisional Application No.60/855,757, filed on Nov. 1, 2006 in the US Patent Trademark Office andKorean Patent Application No. 10-2007-0078047, filed on Aug. 3, 2007 inthe Korean Intellectual Property Office, the disclosure of which isincorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Methods and apparatuses consistent with the present invention relate towireless communications, and more particularly, to wirelesscommunications that support a high-rate data transmission.

2. Description of the Related Art

The demand for the transmission of mass multimedia data in a wirelessnetwork has increased, and there is a greater need for research whichwould result in an effective transmission method in a wireless networkenvironment. Additionally, the need for the wireless transmission ofhigh-quality video, such as a digital video disk (DVD) video, a highdefinition television (HDTV) video, or the like, among various homedevices, has increased.

Presently, an IEEE 802.15.3c task group is considering a technicalstandard for transmitting mass data in a wireless home network. Thisstandard, called Millimeter Wave (mmWave), uses an electric wave havinga physical wavelength of several millimeters to transmit of the massdata (that is, an electric wave having a frequency of 30 GHz to 300GHz). In the related art, this frequency band is an unlicensed band andhas limited use, for example, in communication carriers, radioastronomy, or vehicle anti-collision.

In the IEEE 802.11b standard or the IEEE 802.11g standard, a carrierfrequency is 2.4 GHz, and a channel bandwidth is about 20 MHz. Further,in the IEEE 802.1a standard or the IEEE 802.11n standard, a carrierfrequency is 5 GHz, and a channel bandwidth is about 20 MHz. Incontrast, in the mmWave, a carrier frequency of 60 GHz is used, and achannel bandwidth is about 0.5 to 2.5 GHz. Accordingly, it can be seenthat the mmWave uses a larger carrier frequency and channel bandwidththan the existing IEEE 802.11 standards. Accordingly, if ahigh-frequency signal having a wavelength in millimeters (MillimeterWave) is used, a high transmission rate of several Gbps can be obtained,and the size of an antenna can be set to be not more than 1.5 mm. Asingle chip including the antenna can then be implemented.

In recent years, the transmission of uncompressed audio and/or video(A/V) data between wireless apparatuses using a high bandwidth of themillimeter wave has been studied. Compressed A/V data is compressed witha partial loss through processes, such as motion compensation, discretecosine transform (DCT) conversion, quantization, variable length coding,and the like, such that portions insensitive to the sense of sight orthe sense of hearing of a human being are eliminated. Accordingly, inthe case of the compressed A/V data, deterioration in image quality dueto a compression loss may occur. Further, A/V data compression anddecompression of the transmitting device and the receiving device shouldfollow the same standard. In contrast, uncompressed A/V data includesdigital values (for example, R, G, and B components) representing pixelcomponents as they are. Accordingly, in the case of uncompressed A/Vdata, vivid image quality can be provided.

As described above, since a large amount of data is transmitted in thehigh frequency wireless communication band, it is important to reducethe waste of wireless resources. Accordingly, there is a need for atechnique that supports a high-rate data transmission more efficientlyin the high frequency wireless communication band.

SUMMARY OF THE INVENTION

Exemplary embodiments of the present invention overcome the abovedisadvantages and other disadvantages not described above. Also, thepresent invention is not required to overcome the disadvantagesdescribed above, and an exemplary embodiment of the present inventionmay not overcome any of the problems described above.

The present invention provides an apparatus and method for wirelesscommunications that support a high-rate data transmission.

According to as aspect of the present invention, there is provided amethod for wireless communications, according to the present invention,which includes generating a packet that includes a plurality ofsub-packets, and outputting the packet using a plurality of transmissionmodes.

According to another aspect of the present invention, there is providedan apparatus for wireless communications, which includes a media accesscontrol (MAC) processing unit providing a plurality of sub-packets; anda transmitting/receiving unit outputting a packet that includes theplurality of sub-packets using a plurality of transmission modes.

As described above, the apparatus and method for wireless communicationsaccording to the present invention can increase the data transmissionefficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects of the present invention will be moreapparent from the following detailed description taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a view illustrating a wireless network according to anexemplary embodiment of the present invention;

FIG. 2 is a view showing bit levels according to an exemplary embodimentof the present invention;

FIG. 3 is a view showing a packet according to an exemplary embodimentof the present invention;

FIG. 4 is a view showing data in a divided state according to anexemplary embodiment of the present invention;

FIG. 5 is a view showing a sub-packet header according to an exemplaryembodiment of the present invention;

FIG. 6 is an exemplary view explaining an application of high ratephysical (PHY) layer (HRP) modes according to an exemplary embodiment ofthe present invention;

FIG. 7 is an exemplary view explaining an application of HRP modesaccording to another exemplary embodiment of the present invention;

FIG. 8 is an exemplary view explaining an application of HRP modesaccording to still another exemplary embodiment of the presentinvention;

FIG. 9 is a flowchart illustrating a wireless communication processaccording to an exemplary embodiment of the present invention; and

FIG. 10 is a block diagram illustrating an apparatus for wirelesscommunications according to an exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings. Theaspects of the present invention and methods for achieving the aspectswill be apparent by referring to the exemplary embodiments to bedescribed in detail with reference to the accompanying drawings.However, the present invention is not limited to the exemplaryembodiments disclosed hereinafter, but can be implemented in diverseforms. The matters defined in the description, such as the detailedconstruction and elements, are nothing but specific details provided toassist those of ordinary skill in the art in a comprehensiveunderstanding of the invention, and the present invention is onlydefined within the scope of the appended claims. In the entiredescription of the present invention, the same drawing referencenumerals are used for the same elements across various figures.

FIG. 1 is a view illustrating a wireless network 100 according to anexemplary embodiment of the present invention. The wireless network 100may be a wireless video area network (WVAN) that can support variousapplications for fast transmission of A/V data. The A/V data to betransmitted through the WVAN may be compressed or uncompressed. Forexample, the A/V data includes uncompressed 1080p A/V, uncompressed1080i A/V, MPEG-2 compressed 1080p A/V, uncompressed 5.1 surround soundaudio, and the like.

The wireless network 100 includes a transmitting device 110 and areceiving device 120. Although FIG. 1 illustrates the wireless network100 composed of the transmitting device 110 and the receiving device120, the present invention is not limited thereto. The wireless network100 may include plural transmitting devices and receiving devices.

The transmitting device 110 and the receiving device 120 are wirelesscommunication devices that can transmit/receive data using wirelessmedia. More specifically, the transmitting device 110 may be a sourcedevice such as a set top box, a Blu-ray Disc (BD) player, a BD recorder,an High Definition Digital Versatile Disc (HD-DVD) player, an HD-DVDrecorder, a Personal Video Recorder (PVR), an HD broadcasting receiver,or the like. The receiving device 120 may be a sink device such as aflat panel display, which includes an Liquid Crystal Display (LCD), aplasma device, and a Digital Lighting Processing (DLP) device, a BDrecorder, an HD-DVD recorder, a PVR, or the like. Of course, the presentinvention is not limited thereto, and the transmitting device 110 andthe receiving device 120 may be implemented by devices of differenttypes.

The devices 110 and 120 of the wireless network 100 can support twokinds of physical layers (PHY), that is, a high-rate PHY (HRP) and alow-rate PHY (LRP). In the wireless network 100, a device that cansupport the LRP only may exist depending on its physical performance.Additionally, a device that supports the HRP but can perform one of datatransmission and data reception using the HRP may exist in the wirelessnetwork 100.

The HRP can be used for a high-rate transmission of data (e.g.,uncompressed A/V data). Preferably, the HRP can support an output ofseveral Gbps. The HRP, in order to adjust an output direction orreceiving direction of a wireless signal, can use an adaptive antennatechnology, and in this case, the wireless signal output from the HRPhas directionality. Accordingly, the HRP can be used for unicast. Sincethe HRP can be used for a high-rate transmission, it is preferable thatthe HRP is used to transmit isochronous data such as uncompressed A/Vdata. However, the exemplary embodiment of the present invention is notlimited thereto, and the HRP can be used to transmit asynchronous data,MAC command, antenna steering information, and upper-layer control datafor A/V devices.

The LRP can be used for a low-rate transmission of data. For example,the LRP can provide a bidirectional link of several Mbps. Since awireless signal output from the LRP is nearly omni-directional, the LRPcan be used for broadcast in addition to the unicast. The LRP can beused to transmit a MAC command that includes low-rate isochronous datasuch as audio, low-rate asynchronous data, a MAC command includingbeacons, an acknowledgement of an HRP packet, antenna steeringinformation, capabilities information, and upper-layer control data forA/V devices.

In one exemplary embodiment of the present invention, the HRP canoperate in diverse transmission modes (hereinafter referred to as “HRPmodes”) that support different signal processing methods. Among the HRPmodes, at least one of a coding mode, a modulation method, and a datatransmission rate may differ. In one exemplary embodiment of the presentinvention, the coding mode includes an equal error protection (EEP) modeand an unequal error protection (UEP) mode. The EEP mode is a codingmode in which the same coding rate is applied to respective bits of datato be transmitted, and the UEP mode is a coding mode in which two ormore coding rates are applied to different bits of data to betransmitted.

For example, in case of an eight-bit video image, as shown in FIG. 2,one sub-pixel component 200 is composed of eight bits. Among them, thebit that expresses the highest degree (i.e., the bit of the uppermostlevel) is the most significant bit (MSB), and the bit that expresses thelowest degree (i.e., the bit of the lowermost level) is the leastsignificant bit (LSB). That is, the respective bits of one-byte (i.e.,eight-bit) data have different significance levels in restoring theimage signal. If an error occurs in a bit having a high significancelevel, a complete restoration of the image signal becomes more difficultthan a case that an error occurs in a bit having a low significancelevel. Accordingly, in order to heighten the error correction effect, itis preferable to apply a lower code rate to the bits having the highsignificance levels than the bits having the low significance levels.For this, the UEP mode can be used.

HRP modes according to an exemplary embodiment of the present inventionare shown in Table 1 as below.

TABLE 1 Coding Rate Transmission Upper Bit Lower Bit Rate of HRP Modula-Level Level Original Mode Encoding tion [7] [6] [5] [3] [2] [1] DataIndex Mode Method [4] [0] (Gb/s) 0 EEP QPSK 1/3 0.97 1 QPSK 2/3 1.94 216-QAM 2/3 3.88 3 UEP QPSK 4/7 4/5 1.94 4 16-QAM 4/7 4/5 3.88 5Retransmission QPSK 1/3 infinite 0.97 6 16-QAM 1/3 infinite 1.94

In Table 1, an HRP mode index is an identifier for identifying arespective HRP mode. In Table 1, if the HRP mode index is in the rangeof “0” to “2”, the EEP mode is used, while if the HRP mode index is inthe range of “3” to “4”, the UEP mode is used. In case of the UEP mode,a coding rate of 4/7 is applied to the upper bit levels, while a codingrate of 4/5 is applied to the lower bit levels. In other words, arelatively low coding rate may be applied to the upper bit levels thanthe lower bit levels. In this case, the error correction effect for theupper bit levels becomes higher than the error correction effect for thelower bit levels.

In addition, HRP mode indexes 5 and 6 are HRP modes that can be usedwhen a transmission error occurs and data is retransmitted. According toTable 1, during the retransmission of the data, a coding rate of 1/3 maybe applied to the upper bit levels having a relatively highsignificance, and the lower bit levels having a relatively lowsignificance may not be transmitted (i.e., the coding rate may beinfinite). In the exemplary embodiment of the present invention, it isalso possible that another HRP mode that includes the UEP mode or theEEP mode is used during the retransmission of the data.

As shown in Table 1, the modulation method such as Quadrature PhaseShift Keying (QPSK), 16-Quadrature Amplitude Modulation (QAM), or thelike may differ according to the respective HRP mode. Also, the datatransmission rate may differ according to the HRP mode.

The HRP modes as shown in Table 1 are merely exemplary, and thus thepresent invention is not limited thereto. Accordingly, HRP modes whichare composed of diverse combination of coding modes, coding rates usedin the respective coding modes, and modulation methods, may furtherexist. The HRP mode table as shown in Table 1 is shared by therespective devices in the wireless network 100. For example, the HRPmode table can be stored in the devices when the devices aremanufactured, or can be inputted to the devices through a specifiedcommunication root after the devices are manufactured. In a mannersimilar to the HRP, the LRP can use diverse LRP modes.

FIG. 3 is a view showing an HRP protocol data unit (HRPPDU) packet 300(hereinafter simply referred to as “HRP packet”) that can be transmittedby a transmitting device 110 using the HRP according to an exemplaryembodiment of the present invention.

The HRP packet includes an HRP header 310, a MAC header 320, an HeaderCheck Sum (HCS) field 330, and a packet body 340. Although notillustrated in the figure, the HRP packet 300 may further include apreamble which can be used when a receiving device 120 that receives theHRP packet 300 performs an automatic gain control, phase estimation, andchannel estimation, and a beam tracking field which can be used when thereceiving device performs a beam tracking work.

The packet body 340 includes one or more sub-packets 350-1, 350-2, . . ., and 350-N, which have the same size. It is preferable that the packetbody 340 has 7 sub-packets. However, this is exemplary, and the numberof sub-packets included in the packet body 340 is not limited to 7.

The transmitting device 110 divides the data to be transmitted intopredetermined sizes in advance, and in this case, the divided pieces ofdata are included in the sub-packets. For example, as shown in FIG. 4,the transmitting device 110 divides video data 410 into several datapieces 420, and generates a plurality of sub-packets that include thedata pieces. If the size of the data to be transmitted is equal to orsmaller than the size of the sub-packet set in advance, thecorresponding data can be included in the sub-packet without beingdivided.

In addition to the video data, audio data, A/V control data, and otheradditional data (e.g., caption data) are also composed of sub-pixels.Here, the A/V control data is data required when the A/V data arenormally transmitted and processed between the source device and thesink device, and may be a message for requestingconnection/disconnection of A/V stream connection, a message forcontrolling reproduction of the A/V data, and information about a device(e.g., device name, device type, and the like).

Referring again to FIG. 3, the MAC header 320 includes an address of thetransmitting device 110 that transmits the HRP packet 300, an address ofthe receiving device 120 that receives the HRP packet 300, and the like.

The HCS field 330 includes HCS information of the HRP header 310 and theMAC header 320.

The HRP header 310 includes information required when the receivingdevice 120 physically processes the HRP packet 300. More specifically,as shown in FIG. 3, the HRP header 310 includes a PHY control field 360,and one or more sub-packet headers 370-1, 370-2, . . . , and 370-N.

The respective sub-packet headers 370-1, 370-2, . . . , and 370-Ninclude information on the sub-packets 350-1, 350-2, . . . , and 350-Nthat are included in the packet body 340. In an HRP packet 300, thenumber of sub-packet headers included in the HRP header 310 is equal tothe number of sub-packets included in the packet body 340. In this case,the sub-packet headers correspond to the sub-packets in the order oftheir arrangement. For example, the first sub-packet header 370-1includes information on the first sub-packet 350-1, and the secondsub-packet header 370-2 includes information on the second sub-packet350-2. In the same manner, the N-th sub-packet header 370-N includesinformation on the N-th sub-packet 350-N.

In one exemplary embodiment of the present invention, the sub-packetheader 370-1, as shown in FIG. 5, includes a length field 510, an HRPmode index field 520, and a sub-packet number field 530. The lengthfield 510 indicates the length of the corresponding sub-packet. The HRPmode index field 520 indicates an HRP mode index of the HRP mode appliedto the corresponding sub-packet. The sub-packet number field 530indicates the number of the corresponding sub-packet. The receivingdevice 120 can confirm the sub-packet number of the respectivesub-packet included in the HRP packet 300 using the sub-packet numberfield 530. Accordingly, if a sub-packet to be retransmitted due to anerror occurrence exists, the receiving device 120 transmits thesub-packet number of the corresponding sub-packet to the transmittingdevice 110. In this case, the transmitting device retransmits thesub-packet that corresponds to the sub-packet number transmitted fromthe receiving device 120.

In FIG. 5, the reference numeral “370-1” denotes the sub-packet header,and other sub-packet headers 370-2, . . . , and 370-N have a similarconstruction to that of the sub-packet header 370-1.

Although not specifically illustrated in FIG. 3, the PHY control field360 may include a beam tracking bit, a UEP mapping bit, a scramblerinitialization seed bit, and the like. The beam tracking bit indicateswhether the HRP packet 300 includes a beam tracking field. For example,if the HRP packet 300 includes the beam tracking field, the beamtracking bit is set to “1”, while if the HRP packet does not include thebeam tracking field, the beam tracking bit is set to “0”. The UEPmapping bit includes information that identifies whether the UEP modeapplied to the sub-packet is a UEP mapping mode or a UEP coding mode.For example, if the UEP mapping mode is applied, the UEP mapping bit isset to “1”, while if the UEP coding mode is applied, the UEP mapping bitis set to “0”. The scrambler initialization seed bit indicates aninitialization seed used when the data to be transmitted is scrambled.

The transmitting device 110 can apply the same HRP mode to allsub-packets included in the HRP packet 300, or apply different HRP modesby sub-packets included in the HRP packet 300. That is, the transmittingdevice 110 can apply one or more HRP modes to one HRP packet 300.Preferably, the HRP mode including the UEP mode is applied to datacomposed of bits having different significance levels such asuncompressed video data, and the HRP mode including the EEP mode isapplied to data composed of bits having the same significance level suchas A/V control data or additional data.

FIGS. 6 to 8 are exemplary views explaining application of HRP modesaccording to exemplary embodiments of the present invention. HRP modesused in FIGS. 6 to 8 are based on the exemplary embodiment as shown inTable 1. In FIGS. 6 to 8, it is exemplified that the HRP packet includesseven sub-packets. However, the number of sub-packets according to thepresent exemplary embodiment of the invention is not limited thereto.

FIG. 6 shows a case that the same HRP mode is applied to all sub-packets641 to 647. In FIG. 6, HRP mode 4 is applied to the sub-packets 641 to647, and thus in consideration of Table 1, a coding work in the UEPmode, in which a coding rate of the upper bit levels is 4/7 and a codingrate of the lower bit levels is 4/5, and a modulation work using 16-QAMcan be performed with respect to the sub-packets 641 to 647. In oneexemplary embodiment of the present invention, the respectivesub-packets 641 to 647 as shown in FIG. 6 include video data.

In the exemplary embodiment of the present invention as shown in FIG. 6,an HRP header 610, a MAC header 620, and an HCS field 630 are processedin HRP mode 0. The HRP header 610, the MAC header 620, and the HCS field630 may also be processed in other HRP modes. However, it is preferredthat the HRP mode including an EEP mode be applied since there is nosignificant difference among bits composing the HRP header 610, the MACheader 620, and the HCS field 630. The HRP mode to be applied to the HRPheader 610, the MAC header 620, and the HCS field 630 may bestandardized among devices in the wireless network 100. Accordingly,although the transmitting device 110 has not informed the receivingdevice 120 of the information about the HRP mode applied to the HRPheader 610, the MAC header 620, and the HCS field 630, the receivingdevice 120 can be aware which HRP mode has been applied to the HRPheader 610, the MAC header 620, and the HCS field 630. Hereinafter,explanation of the HRP mode applied to the HRP header 610, the MACheader 620 and the HCS field 630 will be omitted.

In the exemplary embodiment of the present invention as shown in FIG. 7,the first sub-packet 741 is processed in HRP mode 1, and the remainingsub-packets 742 to 747 are processed in HRP mode 3. Accordingly, inconsideration of the exemplary embodiment as shown in Table 1, a codingwork in the EEP mode, in which a coding rate is 2/3, and a modulationwork using QPSK can be performed with respect to the first sub-packet741. Also, a coding work in the UEP mode, in which a coding rate of theupper bit levels is 4/7 and a coding rate of the lower bit levels is4/5, and a modulation work using QPSK can be performed with respect tothe second to seventh sub-packets 742 to 747. In one exemplaryembodiment of the present invention, the first sub-packet 741 includesaudio data, and the remaining sub-packets 742 to 747 include video data,as shown in FIG. 7.

In the exemplary embodiment of the present invention as shown in FIG. 8,HRP mode 1 is applied to the first three sub-packets 841, 842, and 843;HRP mode 5 is applied to the fourth sub-packet 844, and HRP mode 3 isapplied to the last three sub-packets 845, 846, and 847. Accordingly, inconsideration of the exemplary embodiment as shown in Table 1, a codingwork in the EEP mode in which a coding rate is 2/3 and a modulation workusing QPSK can be performed with respect to the first three sub-packets841, 842, and 843. Also, a coding work in which a coding rate of theupper bit levels is 1/3 and a modulation work using QPSK can beperformed with respect to the fourth sub-packet 844. In addition, acoding work in the UEP mode, in which a coding rate of the upper bitlevels is 4/7 and a coding rate of the lower bit levels is 4/5, and amodulation work using QPSK can be performed with respect to the lastthree sub-packets 845, 846, and 847. In one exemplary embodiment of thepresent invention, the first three sub-packets 841, 842, and 843 includeA/V control data, additional data, and audio data, respectively, and thefourth sub-packet 844 includes video data to be retransmitted. The lastthree sub-packets 845, 846, and 847 include new video data.

As described above, different HRP modes are applied to the sub-packetsaccording to the data types included in the sub-packets. It is alsopossible to properly modify the HRP modes according to the wirelessenvironment. The application of HRP modes as shown in FIGS. 6 to 8 ismerely exemplary, and thus the exemplary embodiment of the presentinvention is not limited thereto.

FIG. 9 is a flowchart illustrating a wireless communication processaccording to an exemplary embodiment of the present invention.

Referring to FIG. 9, the transmitting device 110 constructs data to betransmitted in the form of sub-packets (S910), and generates a packetthat includes the sub-packets (S920). A header of the generated packetincludes identifiers of transmission modes to be applied to therespective sub-packets. For example, the packet generated at operationS920 may be the HRP packet as described above with reference to FIG. 3.

During the packet generation, the transmitting device 110 performs agrouping of sub-packets having the same transmission mode, and includesthe grouped sub-packets in a packet body. That is, the transmittingdevice 110 arranges the sub-packets which have data of similar typesadjacent to each other in the packet body. For example, in the exemplaryembodiment of the present invention as shown in FIG. 7, the sub-packets742 to 747 to which HRP mode 3 is applied are arranged in an adjacentmanner, and in the exemplary embodiment of the present invention asshown in FIG. 8, the sub-packets 841, 842, and 843, to which HRP mode 1is applied, and the sub-packets 845, 846, and 847, to which HRP mode 3is applied, are adjacently arranged in groups.

Preferably, the transmitting device 110 arranges the sub-packets thatinclude data sensitive to an error, such as audio data and A/V controldata, at the head of the packet body. This can be confirmed through theexemplary embodiments as shown in FIGS. 7 and 8.

More specifically, it is assumed that one packet includes fivesub-packets. The transmitting device 110 generates a packet includingsub-packets 1 to 5. If sub-packets 1, 3, and 5 are normally received inthe receiving device 120, but sub-packets 2 and 4 including video dataare lost as a result of the transmitting device's transmission of apacket to the receiving device 120, the transmitting device 110 cangenerate a next packet that includes the lost sub-packets 2 and 4 andnew sub-packets 6, 7, and 8. If the sub-packet 6 includes audio data orA/V control data and the sub-packets 7 and 8 include video data, thesub-packets 2, 4, 6, 7, and 8 are arranged in the packet body in amanner that the sub-packet 6 is positioned at the head of the packetbody and the sub-packets 2, 4, 7, and 8 including the video data followthe sub-packet 6. In this case, the order of arrangement of thesub-packets including the video data is determined according to thesub-packet numbers. That is, the order of arrangement of the sub-packets2 and 4 to be retransmitted and the new sub-packets 6, 7, and 8 may bedetermined in the order of 6→2→4→7→8. This is merely exemplary, and thepresent invention is not limited thereto.

Since there is no significant difference among the bits composing theaudio data, an EEP mode may be applied thereto. In the case of A/Vcontrol data, the EEP mode may also be applied. Therefore, if thesub-packets including the audio data or A/V control data are arranged atthe head of the packet body, the sub-packets may be processed in the HRPmode, which is the same as the MAC header.

When the packet is generated, the transmitting device 110 processes thepacket using a plurality of transmission modes (S930), and wirelesslyoutputs the processed packet (S940). At operation S940, the transmittingdevice 110 may perform signal processing operations (e.g., signal codingand signal modulation) by sub-packets.

When the packet is transmitted from the transmitting device 110, thereceiving device 120 can confirm the transmission modes applied to therespective sub-packets through the header of the packet (S950). Then,the receiving device 120 processes the sub-packets using signalprocessing modes that correspond to the confirmed transmission modes(S960). As a result of processing the sub-packets, the receiving device120 can acquire the data included in the respective sub-packets.

If the transmitting device 110 has applied plural transmission modes toone packet, the receiving device 120 can process the received packet inplural signal processing modes. Here, the signal processing modecorresponds to the transmission mode of the transmitting device 110. Forexample, if the transmitting device 110 has processed the packet usingthe coding mode and the modulation method in the exemplary embodiment ofthe present invention as shown in Table 1, the receiving device 120 canuse the corresponding decoding mode and demodulation method.

FIG. 10 is a block diagram illustrating an apparatus 1000 for wirelesscommunications according to an exemplary embodiment of the presentinvention.

The wireless communication apparatus 1000 as shown in FIG. 10 may be thetransmitting device 120 or the receiving device 120 as described above.The wireless communication apparatus 1000 includes a CPU 1010, a storageunit 1020, an MAC processing unit 1040, and a transmitting/receivingunit 1050.

The CPU 1010 controls other components connected to a bus 1030, andserves to process data on upper layers (e.g., a logical link control(LLC) layer, a network layer, a transmission layer, an applicationlayer, and the like) of the MAC layer among general communicationlayers. Accordingly, the CPU 1010 processes received data provided fromthe MAC processing unit 1040, or generates transmitted data and providesthe generated data to the MAC processing unit 1040. For example, thedata generated or processed by the CPU 1010 may be uncompressed A/Vdata.

The storage unit 1020 stores the received data processed by the CPU1010, or stores the transmitted data generated by the CPU 1010. Thestorage unit 1020 may be implemented by a nonvolatile memory device suchas a ROM, a PROM, an EPROM, and a flash memory, a volatile memory devicesuch as a RAM, a storage medium such as a hard disc and an optical disc,or another memory known in the related art.

The MAC processing unit 1040 generates sub-packets using data providedfrom the CPU 1010, and transfers the generated sub-packets to thetransmitting/receiving unit 1050. If the CPU 1010 provides thesub-packets, the MAC processing unit 1040 may transfer the sub-packetsto the transmitting/receiving unit 1050. The MAC processing unit 1040can determine the order of arrangement of the sub-packets so that thesub-packets including data of similar types are adjacently arranged inthe packet body.

In addition, the MAC processing unit 1040 transfers data included in thesub-packets provided from the transmitting/receiving unit 1050 to theCPU 1010. If plural sub-packets are provided, the MAC processing unit1040 may combine data pieces included in the respective sub-packets intoone data.

The transmitting/receiving unit 1050 transmits the packet including thesub-packets provided from the MAC processing unit 1040 to anotherwireless communication apparatus. Additionally, thetransmitting/receiving unit 1050 receives a packet transmitted fromanother wireless communication apparatus, and transfers the sub-packetsincluded in the received packet to the MAC processing unit 1040. Morespecifically, the transmitting/receiving unit includes a packetprocessing unit 1051 and a physical processing unit 1052.

The packet processing unit 1051 generates a packet including thesub-packets provided from the MAC processing unit 1040. The packetgenerated by the packet processing unit 1051 may be the HRP packet asdescribed above with reference to FIG. 3. That is, the packet processingunit 1051 determines the transmission mode (e.g., one among HRP modes asshown in Table 1) to be applied to the sub-packets according to the typeof data included in the sub-packet, and sets the identifier of thedetermined transmission mode in the header of the packet. Also, thepacket processing unit 1051 informs the physical processing unit 1052 ofthe transmission mode to be applied to the sub-packets.

In addition, the packet processing unit 1051 confirms the transmissionmode applied to the sub-packets included in the packet by analyzing theheader of the received packet transmitted from another wirelesscommunication apparatus. Through this, the packet processing unit 1051informs the physical processing unit 1052 what signal processing modeshould be applied to the respective sub-packets. Also, the packetprocessing unit 1051 extracts the sub-packets from the received packet,and transfers the extracted sub-packets to the MAC processing unit 1040.

The physical processing unit 1052 performs a signal processing operationfor transmitting the packet being transferred from the packet processingunit 1051, and wirelessly outputs the processed packet using an antenna1053. The signal processing operation is performed for the header of thepacket and the respective sub-packets. The signal processing operationincludes signal coding and signal modulation operations. The physicalprocessing unit 1052 processes the header of the packet and therespective sub-packets in a coding mode and modulation method under thecontrol of the packet processing unit 1051. Even without the control ofthe packet processing unit 1051, the physical processing unit 1052 mayprocess the header of the packet using the coding mode and modulationmethod previously set by default.

In addition, the physical processing unit 1052 receives a packettransmitted from another wireless communication apparatus through theantenna 1053, and performs a signal processing of the received packet.The signal processing operation includes signal demodulation and signaldecoding operations. The particular demodulation method and decodingmode the physical processing unit 1052 uses may be determined under thecontrol of the packet processing unit 1051. Even without the control ofthe packet processing unit 1051, the physical processing unit 1052 mayprocess the header of the packet using the demodulating method anddecoding mode previously set by default. The physical processing unit1052 may be implemented by the HRP. Although not illustrated in thedrawing, the wireless communication apparatus 1000 may include anotherphysical processing unit implemented by the LRP.

The components of the wireless communication apparatus 1000 as describedabove with reference to FIG. 10 can be implemented by modules. The term“module”, as used herein, means, but is not limited to, a software orhardware component, such as a Field Programmable Gate Array (FPGA) orApplication Specific Integrated Circuit (ASIC), which performs certaintasks. A module may advantageously be configured to reside on theaddressable storage medium and configured to execute on one or moreprocessors. Thus, a module may include, by way of example, components,such as software components, object-oriented software components, classcomponents and task components, processes, functions, attributes,procedures, subroutines, segments of program code, drivers, firmware,microcode, circuitry, data, databases, data structures, tables, arrays,and variables. The functionality provided for in the components andmodules may be combined into fewer components and modules or furtherseparated into additional components and modules.

Although exemplary embodiments of the present invention have beendescribed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

What is claimed is:
 1. A method for wireless communications, the methodcomprising: generating a packet that comprises a plurality ofsub-packets; and outputting the packet using a plurality of transmissionmodes, wherein the outputting the packet comprises: processing theplurality of sub-packets in any one of the plurality of transmissionmodes; and transmitting the packet including the processed sub-packetsto a receiving device, and wherein the transmission modes are high ratephysical layers (HRP) mode which support different processing methods,and the packet comprises a packet body and a packet header, the packetbody comprises the plurality of sub-packets, and the packet headercomprises a plurality of sub-packet headers having information on therespective sub-packets.
 2. The method of claim 1, wherein at least oneof a coding mode, a modulation method, and a transmission rate differsamong the plurality of transmission modes, and the coding mode includesan equal error protection mode in which a same coding rate is applied toall bits of data, and an unequal error protection mode in which at leasttwo coding rates are applied to different bits of the data.
 3. Themethod of claim 1, wherein each of the plurality of sub-packet headerscomprises at least one of a length of a corresponding sub-packet, anidentifier of the transmission mode to be applied to the correspondingsub-packet, and a sub-packet number of the corresponding sub-packet. 4.The method of claim 1, wherein the plurality of sub-packets are groupedby sub-packets to which a same transmission mode is applied, and areincluded in the packet, and each of the plurality of sub-packetscomprises at least one of video data, audio data, audio or video controldata, and additional data.
 5. The method of claim 1, wherein theplurality of sub-packets comprises a first sub-packet comprising audiodata or audio or video control data and a second sub-packet comprisingvideo data, and an order of arrangement of the first sub-packet precedesan order of arrangement of the second sub-packet in the generatedpacket.
 6. An apparatus for wireless communications, the apparatuscomprising: a media access control processing unit which generates aplurality of sub-packets; and a transmitting unit which outputs a packetthat comprises the plurality of sub-packets using a plurality oftransmission modes, wherein the outputting the packet comprises:processing the plurality of sub-packets in any one of the plurality oftransmission modes; and transmitting the packet including the processedsub-packets to a receiving device, and wherein the transmission modesare high rate physical lavers (HRP) modes which support differentprocessing methods, and packet comprises a packet body and a packetheader, the packet body comprises the plurality of sub-packets, and thepacket header comprises a plurality of sub-packet headers havinginformation on the respective sub-packets.
 7. The apparatus of claim 6,wherein at least one of a coding mode, a modulation method, and atransmission rate differs among the plurality of transmission modes, andthe coding mode includes an equal error protection mode in which a samecoding rate is applied to all bits of data, and an unequal errorprotection mode in which two or more coding rates are applied todifferent bits of the data.
 8. The apparatus of claim 6, wherein each ofthe plurality of sub-packet headers comprises at least one of a lengthof a corresponding sub-packet, an identifier of the transmission mode tobe applied to the corresponding sub-packet, and a sub-packet number ofthe corresponding sub-packet.
 9. The apparatus of claim 6, wherein theplurality of sub-packets are grouped by sub-packets to which the sametransmission mode is applied, and are included in the packet.
 10. Theapparatus of claim 6, wherein each of the plurality of sub-packetscomprises at least one of video data, audio data, audio or video controldata, and additional data.
 11. The apparatus of claim 6, wherein theplurality of sub-packets comprise a first sub-packet comprising audiodata or audio or video control data and a second sub-packet comprisingvideo data, and an order of arrangement of the first sub-packet precedesan order of arrangement of the second sub-packet in the generatedpacket.